Lebesgue integration, real analysis problem. Solve the(b) part of the problem and explain in detail,please.

(a) Let f and g be integrable functions defined on A EM. Let {fn} and {gn} be sequences of simple functions so that fn f and gn →g uniformly on A. Show that fn + en + f + g uniformly on A. (6) Use the result from (a) and the definition of integrability to show that SA f + g = ld f + SA g for all functions f and g integrable on A EM.